1. Field of the Invention
The present invention relates to a data recording/ reproducing system for encoding binary data to record the encoded data as an image and for reading the recorded image and decoding the read image into binary data.
2. Description of the Related Art
A bar code technique is known as a technique for reading an encoded image from a recording medium (recording sheet) and reproducing binary data.
For example, the technique is disclosed in U.S. Pat. Nos. 4,422,361, 4,437,378, and 4,464,966. However, the bar code is not suitable for inputting a large volume of data since it is difficult to increase a recording density of bar codes in terms of their specific format.
Published Unexamined Japanese Patent Application No. 53-73026 discloses a technique wherein an image constituted by some black dots and the remaining white dots of an i.times.j (e.g., 3.times.3) matrix is read to recognize a black-and-white mesh pattern. The data volume of the matrix encoded image can be increased by increasing the number of dots included in the matrix. However, in the above patent application, in order to recognize the black-and-white mesh pattern, software is used. For this reason, the technique requires a considerable time to recognize a pattern, and a pattern reading apparatus becomes expensive. A data recording technique using a similar matrix image is also described in "Dump List Read by Image Scanner", I/O, May 1988, pp. 121 to 125.